202 FRIB Graduate Brochure

Kaitlin Cook
Assistant Professor of Physics
Keywords: Near-Barrier Nuclear Reaction Dynamics, Weakly-Bound Nuclei,
Fusion, Fission, Charged Particle Detectors.
Experimental Nuclear Physics
About
• BSc (Advanced) (Honours), Physics and Astronomy
& Astrophysics, The Australian National University,
2012
• PhD, Nuclear Physics, The Australian National
University, 2017
• Joined the laboratory in 2020
• cookk@frib.msu.edu
Research
My group studies reactions at energies near the fusion
barrier, where the structure of colliding nuclei have
profound influence on reaction outcomes. We have two
areas of focus. Firstly, we aim to understand nuclear
reactions of exotic nuclei that are “weakly-bound”, having
low thresholds to removing some number of protons and
neutrons. Some of these nuclei even have “halos” of nuclei
around a central core. Their reaction outcomes are very
different compared to those of regular nuclei. As more
exotic weakly-bound isotopes become accessible at FRIB,
it is becoming critical to understand the role of weakbinding
and associated cluster structures in reactions.
In addition, we study processes that prevent superheavy
element production. The evaporation residue crosssections
in reactions forming the heaviest superheavy
elements are extremely small. This is primarily because
of separation of nuclei before they can fully equilibrate
(quasifission). In quasifission, small changes in nuclear
properties of the colliding nuclei have a huge effect on the
time-scale and probability of quasifission. It is therefore
crucial to understand the effect of the nuclear structure
of colliding nuclei on quasifission outcomes.
In both cases, we learn a lot about reactions by performing
clever experiments that measure the energy and angular
correlations of charged particles. In doing so we infer a lot
of information about when, where, and how breakup occurs.
Biography
I’m originally from Perth in Western Australia, and I
completed my undergraduate degree, PhD, and first
postdoc in the Nuclear Reactions group at the Australian
National University in Australia’s capital city, Canberra.
There, I became interested in nuclear reactions that occur
at energies near the fusion barrier. At these energies, the
outcomes of nuclear reactions are extremely sensitive
probes of the interplay between nuclear structure and
reaction dynamics. This interplay can enhance fusion
cross-sections by a factor of ~100!
After my time at the ANU, I was a JSPS fellow at Tokyo
Institute of Technology in Japan, where I studied the
structure of exotic nuclei that have very extended
matter distributions – “halo nucle”. Now at FRIB, I like to
combine my interests and study the influence of exotic
nuclear structures on reaction outcomes at near-barrier
energies. Designing experiments that help us understand
the huge variety of phenomena that occur is a significant
intellectual challenge. Our knowledge of nuclear reactions
has important consequences on understanding the origins
of the elements, choosing the right reaction for making
the next superheavy elements, and in uses of nuclear
reactions for society.
How Students can Contribute as Part
of my Research Team
PhD projects are available in studying reactions with
weakly bound nuclei and in studying the processes that
prevent superheavy element creation. Students in the
group contribute to the development of new detector
systems and analysis methods to measure breakup,
fusion, and fission with beams from ReA6 provided by
FRIB. Complementing the discovery physics performed
at FRIB, students will also run and analyze precision
stable beam experiments held at the Australian National
University, as well as collaborate with reaction theorists.
The larger “palette” of nuclei that will be available with
FRIB means that we are entering an exciting new era for
near-barrier reaction studies. The main tool for these
studies are large-acceptance position-sensitive chargedparticle
detectors, which allow us to measure energy
and angular correlations of charged particles produced
in nuclear reactions.
Selected Publications
Origins of Incomplete Fusion Products and the
Suppression of Complete Fusion in Reactions of 7Li K.J.
Cook, E.C. Simpson et al. Phys. Rev. Lett. 122 102501 (2019)
Interplay of charge clustering and weak binding in
reactions of 8Li. K.J. Cook, I.P. Carter et al. Phys. Rev. C. 97
021601(R) (2018)
Zeptosecond contact times for element Z=120 synthesis,
H.M. Albers et al. Physics Letters B. 808 135626 (2020)
45
2022_FRIB_Graduate_Brochurev4.indd 45
10/29/2021 3:33:51 PM